Matter

Matter

• Pure Substances: Substances that cannot be broken down into simpler substances.

  • Examples: Sugar, Salt, Copper, Silicon

• Elements: Basic substances, e.g. Copper, Silicon

• Compounds: Formed from two or more elements.

  • Examples: Sugar, Salt

• Mixtures: Physical combinations of two or more substances not chemically bonded.

  • Heterogeneous Mixtures: Visibly different substances, e.g. Sand and Water, Oil and Water.

  • Homogeneous Mixtures: Uniform composition, e.g. Salt Water, Steel.

Types of Elements

• Metals: Good conductors of electricity and heat; shiny surface; solid at room temperature (except Hg).

  • Example: Copper

• Metalloids: Properties of both metals and non-metals, e.g. Silicon.

• Non-Metals: Dull surface, poor conductors, can be gas, liquid, or solid at room temperature.

  • Example: Sulfur

Chemical Bonds

• Ionic Bonds: Formed when one or more electrons are transferred from a metal to a non-metal.

• Covalent Bonds: Formed when electrons are shared between atoms.

Phases of Matter

• Solids: Fixed shape; cannot flow; high density.

• Liquids: Take shape of container; fixed volume; can flow.

• Gases: No fixed shape or volume; low density; can flow.

Kinetic Molecular Theory

• Matter consists of particles in constant motion.

• Temperature measures average kinetic energy.

• Phase changes occur with energy changes in particles.

Electron Configuration

• Atoms have electrons in different orbitals: s, p.

• Configuration follows the order: 1s, 2s, 2p, 3s, 3p.

Chemical Properties

• Electronegativity: Attractiveness for electrons in a bond, increases left to right in periodic table.

• Ionization Energy: Energy required to remove an electron, increases left to right, decreases top to bottom.

Types of Chemical Bonds

1. Covalent Bonds: Formed between non-metals; share electrons.

2. Ionic Bonds: Transfer of electrons between metals and non-metals to form ions.

3. Metal Bonds: Delocalized electrons; form between metals, conductive properties.